It is so infrequent that automated communications are nice that I enjoy celebrating every instance. I had put my Netflix account on hold last month, but mailed back what turned out to be an empty envelope. I assumed they had already charged me the $14 for the missing DVD -- how many companies would've done just that? -- but instead I get this reminder from a friendly robot.

As part of Hill's Beacon initiative, I traveled to the Y Combinator's Ad Innovation Conference earlier this week to watch some 20 YC-funded start-ups present their technologies to a roomful of ad people. AdExchanger already has a nice write-up that explains what each company does, so that's not what I am going to do here. Instead, I will go through my notes trying to answer the question Paul Graham, the YC co-founder (pictured above with the glass), asked after the event: "So, what stuck?"